Puzzled by phase of Marantz 40n + KEF R3

[cmattarei]

I have a Marantz 40n and a pair of KEF R3, and I bought an SVS 3000 micro to fill in the low end. While in the process of tuning in phase, gain, etc I have noticed that my left and right speakers seem to have a difference in phase. I have accurately placed and measured the speakers location and I am using REW with a Mac connected to the line in with a Dayton Audio iMM-6C mic to double check my ears. How is that possible? Can it be the room? Any ideas?

 

[radiomike]

Room size and shape and the location of speakers within the room will have some affect on your measurement. Also individual variation between speakers will have some affect on measurement.

However, your measurement doesn't have a timing reference. This is probably what you are seeing, I'm not overly familiar with REW myself, but have a look at "acoustic timing reference" in the REW help/docs.

 

[cmattarei]

That's a good catch! I am pretty new with REW and I have missed the time alignment. However, I can actually hear that if I play a 55Hz tone the null between speaker and sub requires a different phase between left and right.

 

[Keith_W]

Welcome to ASR! Please see the eBook in my signature. You will need independent measurements of your sub, left speaker, and right speaker, all with a timing reference.